Implement suspend() and resume() for OfflineAudioContext

third_party/WebKit/Source/modules/webaudio/DeferredTaskHandler.cpp

Index: third_party/WebKit/Source/modules/webaudio/DeferredTaskHandler.cpp
diff --git a/third_party/WebKit/Source/modules/webaudio/DeferredTaskHandler.cpp b/third_party/WebKit/Source/modules/webaudio/DeferredTaskHandler.cpp
index cba5a99247ab2929a07aae6107dbb4a70cfee023..bf47d8939c96665a49fa4877377e57e79906f34b 100644
--- a/third_party/WebKit/Source/modules/webaudio/DeferredTaskHandler.cpp
+++ b/third_party/WebKit/Source/modules/webaudio/DeferredTaskHandler.cpp
@@ -60,6 +60,16 @@ void DeferredTaskHandler::unlock()
     m_contextGraphMutex.unlock();
 }
 
+void DeferredTaskHandler::offlineLock()
+{
+    // It is safe to lock the audio thread for offline rendering, but
+    // let us have RELEASE_ASSERT here to make sure to explicitly crash rather
+    // than accidentally blocking the audio thread.
+    RELEASE_ASSERT(isAudioThread());

[Raymond Toy, 2015/10/21 18:22:45]

Maybe use RELEASE_ASSERT_WITH_MESSAGE so a simple message is printed before we
crash.  Then we get some useful information even if the stacktrace is broken for
some reason.

[hongchan, 2015/10/22 18:23:48]

Done.

+
+    m_contextGraphMutex.lock();
+}
+
 #if ENABLE(ASSERT)
 bool DeferredTaskHandler::isGraphOwner()
 {